OBJECTIVETo investigate the influence of alpha smooth muscle actin fusion protein (alpha-SMA-FP) on fibroblast contraction, in order to find a new way to control scar contracture.

METHODSThree dimensional gel culture model of fibroblasts populated collagen lattices (FPCLs) was employed in the study. The fibroblasts were cultured in gel for 5 days. The cells in experimental group were processed by alpha-SMA-FP in dose of 5, 10, 50, 100 and 250 mg/L, respectively. The cells were therefore divided into E(1), E(2), E(3), E(4) and E(5) groups. Blank control was set to be C(1) group, and the cells processed by 250 mg/L of alpha-SMA-FP be C(2) group. The contraction rate was calculated by measuring the diameters of the gel before and after the procession. The change of contraction rate in E5 group was observed after the alpha-SMA-FP being rinsed out. Immunofluorescent staining of alpha-SMA-FP was carried out in fibroblasts.

RESULTSThe contraction rate in C1 and C2 groups showed no difference, being (58.6 +/- 3.1)% and (56.2 +/- 4.9)% respectively, while that in E1 to E5 groups was (45.56 +/- 4.1)%, (42.3 +/- 4.2)%, (41.8 +/- 3.6)%, (37.6 +/- 5.8)% and (26.4 +/- 4.7)%, respectively. However, the contraction rate in E5 was (53.3 +/- 5.6)% after the alpha-SMA-FP had been rinsed out. The difference of the rates among control group and experimental groups, especially in E5 after alpha-SMA-FP being rinsed out, was significant (P < 0.05 or 0.01). alpha-SMA-FP was located on the fibers of the fibroblasts as shown by staining, while the alpha-SMA was not stained. Nevertheless, the staining was obvious in control group.

CONCLUSIONalpha-SMA-FP could inhibit the contraction of fibroblasts specifically with dose dependent effect.